Network and protocol for controlling washing and drying machines which share common utilities

ABSTRACT

A system for controlling a plurality of washing machines in a laundry facility which share a common resource. A plurality of autonomously operated washing machines are connected through a network, so that a slave controller of each washing machine may be controlled by a master controller of the network. The master controller issues periodic polling commands over the network to obtain status information from each of the washing machines. Each slave controller of the washing machine can be prohibited from proceeding through a washing cycle when a common resource used by all machines has reached capacity limits.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on provisional application No. 60/546,187,filed Feb. 23, 2004, and claims priority thereto.

The present invention relates to operating multiple machines of alaundry facility. Specifically, a system and network protocol aredisclosed for controlling laundry machines which use a common resource.

Large laundry facilities utilize numerous washing/drying machines whichnecessarily share common utilities, such as power and/or a drain. As thenumber of machines in a facility increases, the ability of the commonresources to adequately service each additional machine is limited. Forinstance, in the case of a common drain used by all washing machines,the drain capacity may be such that only a certain number of machinesmay discharge wash water at a given time. Accordingly, the facility mustinclude a way to avoid an overload of any common resources such as adrain, and it is necessary to avoid completely autonomous operation ofeach machine.

The overload of common resources may only be temporary. For instance,washing machines, or drying machines in a laundry facility, may only bedraining or using an excessive amount of power during a portion of theirwashing/drying cycle. In the case of the drain, it is only used todischarge water following the washing cycle or the rinse cycle.Accordingly, it is not necessary to limit the number of machines in afacility if there is a way of controlling how many machines will use aparticular resource at the same time. Thus, in the case of the drain, amachine needing the drain may be inhibited until such time as the draincapacity is available.

In the case of a facility that has a limited power service, such as 60amp service for instance, the total number of machines serviceable bythe facility would normally be limited. However, by recognizing that themachines are power intensive only during portions of their machinecycles, it is possible to inhibit a machine from entering a powerintensive portion of its operational cycle if inadequate power isavailable for the machine. The present invention has been implemented toprovide a central control facility for monitoring the usage of commonresources to prevent exceeding their capacity.

BRIEF SUMMARY OF THE INVENTION

A system is provided for controlling a plurality of washing machines ina laundry facility which share a common resource. A plurality ofautonomously operated washing machines are connected via a network to anetwork controller. The washing machines each include a slave controllerwhich monitors operation of the washing machine, collects statusinformation regarding the washing cycle of a machine and reports theinformation to the network controller. The network controller determinesfrom the status information how many machines are using a commonresource. The network controller issues commands prohibiting a washingmachine from using a common resource when the previously received statusinformation of the washing machines using a common resource indicatesthe capacity of the common resource to service washing machines has beenreached.

The invention also includes a method for sharing resources among theplurality of laundry machines. A common network connects a slave deviceof the laundry machine to a controller which is common to all machines.The controller receives data indicating the number of machines using theshared resource, and if the number of machines has exceeded the capacityof the shared resource to service additional machines, the controllercan inhibit any additional machines from attempting to use the sharedresource. The additional machines may be placed in a waiting mode andare later authorized to use the shared resource when the number ofmachines using the resource has decreased by one.

In accordance with a preferred embodiment of the invention, a commondrain is used by all machines of a laundry facility, and the controllerreceives information from each machine as to the portion of a laundrycycle being executed by the machine. When the drain is handling amaximum number of machines, additional machines are prohibited fromentering a drain cycle until the number of machines in a drain cycle isbelow the maximum number. While the preferred embodiment is describedwith respect to one resource, a common drain, the features of theinvention may be utilized to avoid exceeding the capacity of otherresources, such as power, or even an exhaust commonly used by aplurality of dryers in a laundry facility.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the inventionillustrating a control system for a plurality of washing/drying machinesof a laundry facility;

FIG. 2 schematically represents the controller and machine networktopology;

FIG. 3 is a flowchart illustrating the process executed by the mastercontroller to determine the wash cycle status of each machine;

FIG. 4 illustrates the process executed at the slave controller of awasher/dryer machine;

FIG. 5 illustrates the process for authorizing a machine to use a commonresource; and

FIG. 6 illustrates the system process for allowing a machine to enter arinse and extract portion of its washing/drying cycle.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Referring now to FIG. 1, there is shown a block diagram of a laundryfacility having a plurality of washing/drying machines 10-13. Theillustrated machines are of the type described more particularly in U.S.patent application Ser. No. 10/428,994, filed May 5, 2003, owned by theAssignee of the present application. Each of the washing/drying machines10-13 have associated with them a controller 18, a door 15 for receivinga wash load and a washing agent compartment 14. The electroniccontrollers 18-21 of each of the washing/drying machines 10-13 include aslave controller, which is capable of transmitting data and receivingdata over the network 17 interconnecting each of the slave controllers18-21 with the master controller 16. The slave controllers 18-21 monitorthe machine cycles, and determine when each of the machines reaches apoint where a shared resource, such as a common drain 30 or increasedpower for the machines is needed. The status of each machinewashing/drying cycle is reported to the master controller 16 where adecision can be made whether or not to authorize one of thewashing/drying machines 10-13 to use the common resource 30. Each of themachines 10-13 have individual drains 24-27 connected to a common drain30 and are connected to a common source of input power. In order toavoid overloading the common drain, or overload the power source, themaster controller 16 will keep track of the number of machines enteringa discharge cycle or a power intensive cycle. When the maximum number ofmachines are discharging wash water into the drain 30, controller 16inhibits additional machines from discharging wash water into the drain30. The system also monitors when a maximum number of machines areentering a power intensive portion of the operational cycle and inhibitsadditional machines from entering the power intensive portion when theinput power will not support additional machines.

FIG. 2 is a schematic representation of the controller 16 networkedusing an industrial network, such as the Allen Bradley IndustrialMachine Network, to each of the washing/drying machines 10-13. Using theapplication information available from the network provider, acontroller 16 and slave interface for controllers 18-21 of each machinemay be realized.

The master controller 16 and slave controllers 18-21 are programmed inaccordance with the steps shown in the flowcharts of FIGS. 3-6. FIGS.3-6 illustrate the embodiment of the invention which permits sharing ofa common drain. Sharing of other resources, such as input power duringpower intensive portions of the washing cycle can be effected usingsimilar programming.

Referring now to FIG. 3, the steps executed by the master controller areillustrated to determine the state of various washing/drying machinesconnected to the network. Once all of the machines have been powered up,and the network controller 16 has entered a communication routine witheach of the slave controllers 18-21, the master controller in step 36continuously polls each of the slave machines for information. When agiven washing/drying machine is entering the discharge portion of thewashing cycle, the master controller is notified as determined from step37. When the master controller has received X drain requests, asdetermined from decision block 38, where X represents a maximum numberof machines which can simultaneously drain at the same time, it notifiesin step 42 the slave controller of any additional washing/dryingmachines that the drain function is at capacity. Step 42 represents thecondition where the slave controller has had a drain permissive removed,thereby inhibiting the drain function of a given washing machine.

Decision block 43 of the master controller determines when a machine hasfinished draining through systematic polls of the slave controllers ofthe machines, and the count of drain requests is reduced by one machine.

At this time, the master controller enables the slave controller of awaiting machine in step 44 to clear the drain permissive which hasinhibited the machine from entering the drain cycle.

The slave controller of a waiting machine initiates in step 39 a drainroutine when the master controller has cleared the drain permissive,previously applied because X machines were determined to already beusing the common drain. When the slave machine finishes a drain routine,the slave controller reports the drain status as having finished to themaster controller which is continuously polling each of the slavecontrollers of the washing machines.

The specific machine cycle and network control provided by the presentinvention for the machines described in accordance with the previouslyidentified patent application is illustrated more particularly in FIGS.4-6. The invention may also be employed in other facilities which useother types of washing machines.

Step 46 of FIG. 4 illustrates that portion of the washing cycle wherethe wash/rinse portion has been engaged. Step 47 illustrates a lintcleaning routine which is used in the aforesaid washing/drying machines.Following the lint cleaning mode, the washer/dryer begins filling for awash cycle in step 48.

Decision block 49 determines whether the washer/dryer has filled to adesired washing level. If so, the washing cycle begins in step 50. Whenthe washing cycle is complete as determined in decision block 51, thewasher then looks to open the drain in step 52. Before the washer canuse its drain function, the master controller has in decision block 53determined whether or not a condition exits, such as a large number ofother machines using the drain, which will prohibit the use of the drainby another machine. If a previously drain inhibit command was initiatedby the master controller in step 56, the machine waits until such timethat the master controller has sensed in step 57 that one of themachines previously in a drain cycle has completed the drain cycle.

When the machine is allowed to drain in step 58, the machine wash cyclegoes into a post wash extract function in step 59. A rinse cycle beginsin step 60 when decision block 61 determines that the desired waterlevel in the machine has been obtained. The rinse cycle completes instep 62, and when decision block 63 indicates it is complete, thewasher/dryer then attempts to drain following the rinse cycle in step64. However, the master controller may have previously inhibited themachine from using the drain if it has sensed in step 65 that X manymachines are using the drain function.

FIG. 6 illustrates the completion of the washing cycle. Step 68 indecision block 69 represents a condition where the machine has beenplaced in the wait state because the drain is at capacity due to othermachines using the drain. Once the master controller determines in step69 that another machine may use the common drain, a waiting machine isauthorized in step 70 by removing a drain permissive previouslyestablished in the slave machine controller. The machine may then gointo a post rinse extract function in step 71. The washer/dryer machineof the referenced patent application may then begin a drying process instep 72.

The foregoing description of the invention illustrates and describes thepresent invention. Additionally, the disclosure shows and describes onlythe preferred embodiments of the invention in the context of a networkand protocol for controlling washing/drying machines which share commonutilities, but, as mentioned above, it is to be understood that theinvention is capable of use in various other combinations,modifications, and environments and is capable of changes ormodifications within the scope of the inventive concept as expressedherein, commensurate with the above teachings and/or the skill orknowledge of the relevant art. The embodiments described hereinabove arefurther intended to explain best modes known of practicing the inventionand to enable others skilled in the art to utilize the invention insuch, or other, embodiments and with the various modifications requiredby the particular applications or uses of the invention. Accordingly,the description is not intended to limit the invention to the form orapplication disclosed herein. Also, it is intended that the appendedclaims be construed to include alternative embodiments.

1. A system for controlling a plurality of washing machines in a laundryfacility which share a common resource, comprising: a plurality ofautonomously operated washing machines; a network connecting a slavecontroller of each of said plurality of washing machines; and a networkcontroller connected to said network for obtaining status informationfrom each of said washing machines, and for transmitting to each slavecontroller connected to said network a command prohibiting a washingmachine from using said common resource based on previously receivedstatus information from other of said washing machines.
 2. A system forcontrolling a plurality of washing machines according to claim 1 whereinsaid network controller determines the number of washing machines whichuse said common resource.
 3. A system for controlling a plurality ofwashing machines according to claim 2 wherein said network controllerdetermines from status information received from said washing machineswhen said common resource is not available for a washing machine to use.4. A system for controlling a plurality of washing machines according toclaim 1 wherein said master controller determines from said statusinformation the number of machines which are simultaneously using saidcommon resource.
 5. A system for controlling a drain function of aplurality of washing machines which use a common drain in a laundryfacility, comprising: a slave controller at each washing machine, saidslave controller controlling said washing machine wash and dry cycles;and a network controller connected via a network to each of said slavecontrollers, said network controller connected to receive informationidentifying the status of each washing machine, said network controllerdetermining from said status how many machines are using said commondrain, and generating an inhibit command for the remaining machinesentering a drain portion of their washing cycle when a predeterminednumber of machines are using said drain to prevent said remainingmachines from draining into said drain.
 6. The system for controllingsaid drain function according to claim 5 wherein said network controllerauthorizes a remaining machine to utilize said common drain when thenumber of machines using said drain drops below said predeterminednumber.
 7. The system for controlling said drain function according toclaim 5 wherein said network controller issues a drain permissivecommand to a remaining one of said washing machines that reports statusinformation indicating that it is entering a drain portion of itswashing cycle when said number of machines using said common drain isbelow said predetermined number.
 8. The system for controlling saiddrain function according to claim 7 wherein each slave controllerdetermines that a drain permissive command has been received beforepermitting a respective washing machine to enter a drain cycle.
 9. In asystem for operating a plurality of laundry machines in a laundry, aslave controller for each washing machine comprising: a laundry cyclecontroller for operating a laundry machine; and a network interface forreceiving commands and transmitting data from and to a networkcontroller, said commands including a permissive which permits saidlaundry machine to enter a portion of a laundry cycle which shares acommon resource with other laundry machines.
 10. The slave controlleraccording to claim 9 wherein said slave controller permissive is removedby a command from said network interface indicating that said sharedcommon resource is unavailable.
 11. The slave controller according toclaim 10 wherein said laundry machine enters said portion of saidlaundry cycle when a subsequent command from said network interfacereestablishes a permissive.
 12. The slave controller according to claim11 wherein following said portion of said laundry cycle, said slavecontroller transmits a completed command to said network controller. 13.A method for sharing resources among a plurality of laundry machineswhich are connected over a common network to a network controller,comprising: determining at a network controller when one or more of saidlaundry machines is entering a portion of a machine cycle requiring ashared resource; determining the number of laundry machines using saidshared resource; determining if the number of machines using said sharedresource is at a maximum; inhibiting any additional machines from usingsaid shared resource when the number of machines reaches said maximum;and authorizing said additional machines to use said shared resourcewhen the number of machines using said resource is less than saidmaximum.
 14. The method for sharing resources according to claim 13wherein said shared resource is a common drain.
 15. The method forsharing resources according to claim 13 further comprising: forwardingstatus information identifying each machine requiring said sharedresource from a slave controller of said laundry machine to said networkcontroller.
 16. The method for sharing resources according to claim 15wherein said network controller inhibits a machine from entering saidportion of a laundry cycle by forwarding a command removing a permissivein said slave controller.
 17. The method for sharing resources accordingto claim 16 wherein said network controller restores said permissive insaid machine entering said portion of a laundry cycle when the number ofmachines using said resource decreases below said maximum.
 18. Themethod for sharing resources according to claim 1 wherein said sharedresource is a common source of input power.